/Engine/Plugins/Developer/PluginUtils/Source/PluginUtils/Public/PluginUtils.h
Validate that the plugin name is valid, that the name isn't already used by a registered plugin and optionally that there isn't an unregistered plugin with that name that exists at the specified location.
static bool ValidateNewPluginNameAndLocation ( const [FString](API\Runtime\Core\Containers\FString) & PluginName, const [FString](API\Runtime\Core\Containers\FString) & PluginLocation, [FText](API\Runtime\Core\Internationalization\FText) * FailReason )